The present invention relates generally to marker poles for subterranean cable installations, and more particularly, to a marker pole having a spring-loaded portion extending above the ground to facilitate movement thereof in response to impacts from motor-vehicles, lawn mowers and the like.
Marker poles are commonly employed for marking the locations of various underground objects. For example, utility lines are often buried in the ground in many locations for aesthetic reasons. Marker poles are placed in the ground and disposed along the buried cable in order to show the location thereof.
In recent years fiber-optic cable networks have been installed in many parts of the country. A common installation procedure involves trenching or boring underground and placing the fiber-optic cables within protective plastic conduit. The fiber-optic cables have many advantages for telecommunications, including the ability to efficiently transmit large amounts of data. However, because relatively high revenues are typically generated from their transfer of correspondingly large amounts of data for telecommunications customers, there exists the potential for large losses in earnings associated with an inoperative fiber-optic cable.
Excavating equipment and operations pose significant threats to buried utility lines, including fiber-optic cables. Natural gas pipelines, for example, pose an explosion risk. Electrical power lines have attendant risks of damage and injuries related to electrical power. Accidentally severing a buried fiber-optic cable can subject an excavation contractor to significant liability for interrupted service. Severing fiber-optic cables can interrupt service unless transmissions can be rerouted. Depending upon the normal traffic volume in a buried cable, significant revenues can be lost before a splice can be made and service restored.
In order to control such risks, utility companies and service providers have marked the locations of their underground lines and provided information regarding same, such as toll-free numbers, which excavators are encouraged to “call before digging”. A common pre-existing type of marker includes a length of plastic pipe with one end embedded in the ground and the other end mounting a cap. The cap can have printed thereon warning information, and can be color-coded for the type of buried utility, e.g.: blue—water; yellow—natural gas; red—electric; orange (white)—fiber-optic, etc. Such utility markers tend to be relatively effective and are widely recognized in the art. Although they are relatively easy to install, many of the prior art designs can be easily destroyed by impact with moveable objects.
In view of the foregoing, there exists a need for a marker pole system that exhibits resistance to inadvertent impacts from motor vehicles, lawn mowers, and the like.